hgweb: pass arguments which a function depends on explicitly in search This changes makes clearer which arguments can a function depend on. Now all the modified functions depend on the 'query' argument only, but future additions will change it.

hgweb: add dynamic search function selection, depending on the query This allows adding other specific search functions, in addition to current keyword search.

unionrevlog: extract 'baserevision' and 'baserevdiff' methods This makes possible to use unionrevlog class with subclasses of revlog that override revlog's 'revision' and 'revdiff' methods. In particular this change is necessary to implement manifest compression, as it allows extension to replace manifest class and override 'revision' amd 'revdiff' methods there.

bundlerevlog: extract 'baserevision' method This makes possible to use bundlerevlog class with subclasses of revlog that override revlog's 'revision' method. In particular this change is necessary to implement manifest compression, as it allows extension to replace manifest class and override 'revision' method there.

solaris: tests can't use tail -n Solaris tail doesn't recognize the -n option. Replace the one use of it with some inline python code, and add a test case to check-code.py.

solaris: sed doesn't recognize a line without a newline

solaris: test cases can't use grep -a The -a option to GNU grep isn't available when using Solaris grep. Replace the one use of grep -a in the testsuite with some in-line Python that does the equivalent, and add a check for grep -a in check-code.py.