Rephrasing and typo fixes.

doc/install.txt

@@ -114,11 +114,10 @@ fails on your machine, you are encouraged to tell us what went wrong on the
 
 .. note::
 
-    `warn.ignore_bug_before=all` remove warning that you don't need to see here.
-    It is also recommended for new user to put this flag to a different value 
-    into their .theanorc file. Go 
-    `here <file:///u/bastienf/repos/Theano/html/library/config.html?libdoc-config#config.warn.ignore_bug_before>`__
-    for detail.
+    `warn.ignore_bug_before=all` removes warnings that you don't need to see here.
+    It is also recommended for a new user to set this flag to a different value 
+    into their .theanorc file.
+    See :attr:`config.warn.ignore_bug_before` for more details.
 
 Troubleshooting: Make sure you have a BLAS library
 -----------------------------------------------------

doc/library/config.txt

@@ -153,23 +153,26 @@ Config Attributes
 
     Default: 'None'
 
-    When we fix a Theano bug that generated bad result in a case, we also make
-    Theano raise a warning when it enconter it again. This help to detect if fixed bug
-    affected your past experiments as you only need to run your experimentand not
-    understands the Theano internal that trigger the bug. A better way to detect
-    that see this will be implemented. See this
-    `ticket <http://trac-hg.assembla.com/theano/ticket/514>`__.
-
-    This flags allo new user to don't get warning about old fixed bug
-    that they don't need. You can set its value to the first version of Theano 
-    that you used(probably 0.3 or higher)
-
-    `None` mean that we should all warning.
-    `all` mean to hide all warning.
-
-    It is recommended that you put a version, so that you will see futur warning.
-    It is also recommended you put this into the .theanorc to have this always
-    actif.
+    When we fix a Theano bug that generated bad results under some
+    circonstances, we also make Theano raise a warning when it encounter
+    the same circonstances again. This helps to detect if said bug
+    had affected your past experiments, as you only need to run your
+    experiment again with the new version, and you do not have to
+    understand the Theano internal that triggered the bug. A better
+    way to detect that see this will be implemented. See this `ticket
+    <http://trac-hg.assembla.com/theano/ticket/514>`__.
+
+    This flag allows a new user not to get warnings about old bugs, that were fixed
+    before their first checkout of Theano.
+    You can set its value to the first version of Theano 
+    that you used (probably 0.3 or higher)
+
+    `None` mean that all warnings will be displayed.
+    `all` mean to hide all warnings.
+
+    It is recommended that you put a version, so that you will see future warning.
+    It is also recommended you put this into the .theanorc, so this setting
+    will always be used.
 
 .. attribute:: home
 

theano/configdefaults.py

@@ -108,15 +108,15 @@ AddConfigVar('experimental.mrg',
 ### To disable some warning about old bug that are fixed now.
 ###
 AddConfigVar('warn.ignore_bug_before',
-             "If None, we warn about all Theano bug found by default. If all we don't warn about Theano bug found by default. If a version, we print warning only for Theano bug found after that version.",
+             "If 'None', we warn about all Theano bugs found by default. If 'all', we don't warn about Theano bugs found by default. If a version, we print only the warnings relative to Theano bugs found after that version. Warning for specific bugs can be configured with specific [warn] flags.",
              EnumStr('None', 'all', '0.3', allow_override=False))
 
 default_0_3 = True
-if config.warn.ignore_bug_before=='None':
+if config.warn.ignore_bug_before == 'None':
     default_0_3 = True
-elif config.warn.ignore_bug_before=='All':
+elif config.warn.ignore_bug_before == 'all':
     default_0_3 = False
-elif config.warn.ignore_bug_before>='0.3':
+elif config.warn.ignore_bug_before == '0.3':
     default_0_3 = False
 
 AddConfigVar('warn.argmax_pushdown_bug',