Ticket #4426: lengths of textfields made similar to the Desktop version, except inside-padding in the textfields (number of characters accomodated) and the case when the Greek letter popup button is shown

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37013 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Ticket #4426: suggesting a textfield padding more fit for 1-length textfields (and consequently, the number of visible characters in the textfields with other lengths as well - to be compatible with the Desktop version)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37014 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Ticket #4426: my previous commit here necessitates this, but this doesn't seem to be in connection with the larger length of textfields when their lengths are greater than 20

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37015 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e