Added tests for GTMNSString+HTML.

These are derived from the tests in google-toolbox-for-mac.
Added tests for GTMURLBuilder.  These are based on google-toolbox-for-mac.

Import some fixes for that class too.  These come from the following
csets in google-toolbox-for-mac:

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r656 | gtm.daemon | 2014-01-29 07:30:07 -0800 (Wed, 29 Jan 2014) | 4 lines

Fix integer formatting compiler warning when building for 64 bit architecture.
The reason is NSInteger is defined as long for 64bit.

DELTA=1  (0 added, 0 deleted, 1 changed)
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r652 | gtm.daemon | 2014-01-17 12:00:18 -0800 (Fri, 17 Jan 2014) | 4 lines

Adding integerValueForParameter to GTMURLBuilder.
Makes it symmetric with setIntegerValue.

DELTA=8  (8 added, 0 deleted, 0 changed)
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r638 | gtm.daemon | 2013-10-03 05:00:22 -0700 (Thu, 03 Oct 2013) | 3 lines

Implement hash function for GTMURLBuilder

DELTA=4  (4 added, 0 deleted, 0 changed)
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r612 | gtm.daemon | 2013-05-06 14:30:09 -0700 (Mon, 06 May 2013) | 3 lines

Fix bug in GTMURLBuilder that doesn't handle url path with escaped characters. E.g. http://www.google.com/path%3AA/path%3AB would become http://www.google.com/path%3AA/path%3AB/path:A/path:B